header{
    width:1240px;
    margin:0 auto;

    display: flex;
    justify-content:space-between;
    align-items: center;

    height:73px;
}
#logo{
    width:165px;
    height:60px;
}

#nav{
    height:100%;

    display: flex;
    align-items: center;
}
#nav ul{
    display: flex;
    height:100%;

    align-items: center;
}
#nav ul li{
    width:99px;
    height:100%;

    display: flex;
    align-items: center;

    margin:0 15px;
    position:relative;
    text-align: center;
}

#nav ul li a{
    font-size:20px;
    margin:0 auto;
    width:100%;

}
#nav ul li i{
    display:block;
    width: 98px;
    height:15px;
    background-image:url("../img/shouyejiaohutiao-icon@2x.png");
    position:absolute;
    bottom:0;
    left:0;

    opacity: 0;
}
#nav ul li i.active{
    opacity: 1;
}